About to start building a Fearless frame up. I’ve been deliberating about a steel gravel/monstercross/birdbiking* build for about the best part of a decade. I’ve obviously chosen the best time to be sourcing drivechain components.

As GRX seems to be traded on the commodities markets above my immediate budget currently, I’m curious about di2 1x as an option. Secondhand. I’m open to 10 speed stuff too.

Anyone had 1x di2 on a drop bike? If so, what were your set ups? Anyone else taken a ‘budget’ (non cable brake) route to a new drop bar build given the current situation? Any advices mucho appreciato.

*My new niche, essentially grabbing my binos and brew kit and heading somewhere peaceful to watch the birds. Say, like heading up above Derwent/Howden in spring to watch the Goshawks display above the forest or some such.

TIA 👍

I’ve just removed the 1x Di2 from my gravel bike in favour of SRAM Rival mechanical, not because it wasn’t good, but because like a complete numpty I dropped the bike (not even a crash!) and broke the right hand shift lever. Replacement parts weren’t available for the latest dura ace shifters and replacement levers are months away still. On the positive I sold the broken lever for £40 less than I paid brand new 3 years ago and the unbroken left hand side I made £50 profit on!

Anyway, my setup. I had dura ace levers and brake callipers (transferred from my old road bike) XT mech. Battery inside the frame and bar end junction box, wu111 wireless sender was hidden inside the left drop (200mm fly lead from junction to wireless sender, then sender to left shifter -> left shifter to junction b inside frame, mech and battery connected to the junction b. R/H shifter cable through bars to junction a in bar end.

XT mechs are cheaper on the used market than GRX (and the single ring grx is basically a re-bodied XT) but shimano stopped supporting it as a setup in the e-tube app when they released GRX, doesn’t stop it working but does remove some of the custom programming options (mainly the ability to tell it what the gear ratios were so it would display on my garmin head unit, not the biggest issue in the world!)

10 speed di2  isn’t compatible with any of the current di2 stuff as it uses different cables. It’s obsolete so I would avoid.

If you are going 1x then there are no compatibility issues,they only arise when you try and mix road and Mtb mechs. Shifters, batteries, control units are all compatible.

So I’d be looking for a mt800 headunit/display and probably an xt rear mech as the cheapest way to get di2 with a decent range cassette.

10 speed di2 isn’t compatible with any of the current di2 stuff as it uses different cables. It’s obsolete so I would avoid.

I thought the old Ultegra levers were (6770?)

10 speed di2 isn’t compatible with any of the current di2 stuff as it uses different cables

Not quite right, 10 speed Dura Ace wiring is not compatible with any other Di2 versions as it uses four wires to make up the cable which can be seen in the plug end

10 speed Ultegra Di2 onwards uses the same wiring as all versions of Di2 after that (2 wires per cable which can be seen in the plug end)

Ive had every version of Dura Ace and Ultegra 10 and 11 speed Di2 over the years and once Shimano swapped to the two wire E tube wiring design on Ultegra 10 speed all Ive ever done is just upgrade the shifters and mechs and carried on using the original 10 speed wiring, battery and junction boxes (now have upgraded to the seatpost battery instead of the old downtube one)

Not quite right

Whoops, sorry about that. A little knowledge etc..

I’m not sure on the mech compatibilites. But what about a trp hylex brakeset with the di2 adapter that allows you to run a climbing shifter on the inside of the lever.

I was thinking of doing that on my upcoming build but now waiting on stock of some SRAM bits due to cost of the di2 stuff.

Br785 are commonly the cheapest Di2 shifter for drop bars and despite being a little ugly, work well. The cheapest RD that you’d really want for 1x will be an XTM8050. You’ll also need either a series of junction boxes, or better yet an MT800 display which also gives you Bluetooth. You’ll then need a DN110 seatpost battery and 3 cables 2 very long (display to battery and display to rear derailleur) and a small one from the right shifter to the display.

Shifters £200, RD £110, battery £80, display £50, cables £45. All eBay prices.

Hey, I started down this path early last year. It wasn’t the brightest idea in light of the inflated lockdown prices for second hand components but I eventually pieced together a 1x setup.

I’ve been meaning to update my build thread on LFGSS Excuse the cut and paste…

The official TRP Hylex bodge for installing climbing shifters in the right hand lever is a bit clunky IMO so I looked in to alternatives. It happens that the newer Dura Ace climbing shifters work without the need for STI levers. Something so simple took an awful lot of Googling so for posterity, the shopping list is as follows:

• SW-R9150 climbing shifters (come as a pair)
• SM-EW90A junction box (3-port, under stem)
• SM-JC41 junction box (meant to be internal but couldn’t fit in seat-tube so currently external)
• RD-R8050 Ultegra rear mech (I don’t think the older 6000 series will work)
• BT-DN110 battery (inside seatpost)
• SM-BCR2 battery charger (something I forgot to factor £££)
• EW-SD50 E-tube cables x3

The Ultegra mech stopped working for no apparent reason afetr a few months. Tried running diagnostics, re-setting the crash mode and a new junction box but it seemed properly dead so now running an XT mech. Bit annoying that something should die for no apparent reason but maybe that’s karma for a mix and match of second hand parts!

Br785 are commonly the cheapest Di2 shifter for drop bars and despite being a little ugly, work well. The cheapest RD that you’d really want for 1x will be an XTM8050. You’ll also need either a series of junction boxes, or better yet an MT800 display which also gives you Bluetooth. You’ll then need a DN110 seatpost battery and 3 cables 2 very long (display to battery and display to rear derailleur) and a small one from the right shifter to the display.

I was running this config on my commuter

The mt800 displays really good also gives you a useful charge port and isn’t that mad looking on a drop bar bike.

I’d also wire both shifters then you can have the sram type shifting or in an emergency if your shifter breaks you have a backup , just for the price of another cable.

The annoying thing about di2 is the cost of the wires 🙂

Di2 battery can also be wrapped in foam and stuffed in downtube, having it in the seatpost can be awkward if your having to travel with bike and need to remove/mess about with seatpost to travel.

Friends mate had an a panic when he severed his wire on a cycling hol to Majorca 🙂

I’ve got mb battery n the head tube. Shimano do a “pro thesis” di2 stem that allows you to run without  a star nut/bung and runs the wires through the stem to the handle bar.

Works really well if you don’t have internal routing for di2.

I have a single cable running from the mt800 to an external junction box under bottom bracket which then feeds the mechs.

I used the di2 cable ducts but helitape is stronger and less visible.

Top stuff. Thanks All. I really like the idea but wonder whether I’m just better ponying up and paying top dollar for some new mechanical shifting/hydro levers.

I’ll have a scoot around eBay etc and see what I can get hold of. All the build looks awesome. Like the idea of the m800 display 👍